Metallic ladder and parts therefor



(No Model.)

F. JOHNSON. METALLIC LADDER AND PARTS THEREFOR.

No. 532,965. Patented Jan. 22, 1895.

Jo .7 1 I l 5 W; 9 0 fi Y \L (57 v 1 l U Ll UNITED STATES PATENT OFFICE.

FERDINAND JOHNSON, on NEW LoNDoN, PENNSYLVANIA METALLIC LADDER AND PARTSTHEREFOR.

SP ECIFICATION forming part Of Letters Patent No. 532,965, dated January22, 1895. Application filed February 2 3, 18 94. Serial No. 501 ,297-(No model.)

and Parts Therefor; and I do hereby declare the following to be asufficiently full, clear, and exact description thereof as to enableothers skilled in the art to make and use said invention.

This invention relates to fire proof ladders adapted to use for fireescape services, and for the general purposes of ladders requiringdurability and strength for climbing, and to stand exposure to theWeather or to heat, and has for its object the making of such ladders ofinterchangeable parts, of forms economically produced from bar metal,and easily erected by persons without any special mechanical skill.

The nature of this invention consists in a combination of step-plates,having notches and perforations therein, formed from flat bars, orangle, or channel iron, interlocked in the openings specially preparedin side strips from angle iron or channel bars, and furtherembraces'oross bars adapted to fit in openings of special form made inthe said side bars, and supporting devices whereby the same is easilyattached to columns, walls, buildings or chimneys, and affordingconvenient means for the attachment of hand rails and casing, forguarding or surrounding the space contiguous to the ladder, andprotecting persons on the ladder from flames, smoke or the weather.

The invention is hereinafter fully described, and illustrated in theaccompanying drawings, in Which- Figure 1 shows a top view of the ladderembodying this invention, as attached to vertical columns or tubes; Fig.2, afront elevation thereof; Fig. 3, a side elevation thereof; Figs.aand 5, two forms of step-plates; Fig. 6, a form of supporting hook;Fig. 7, an enlarged View of a portion of a side plate containing theaperture adapted to receive a step-plate, and a supporting cross piece,Fig. 8, an enlarged side view of a portion of a side-plate showing theaperture adapted to receive and hold the step-plates as cut from angleiron; Fig. 9, an

marked 2, of angular form, and with a projection therein marked 3,adapted to fit in an opening 4, in the step-plates marked 5. The lattermay be beveled, as shown, to save metal and make them lighter.

The opening 2 is of such dimensions that the endof the step-plate may beintroduced horizontally over the projection or pin 3, and then droppeddownwardly on the pin 3, which may be afterward riveted, or bent so asto secure the step-plate in position The terminal openings 6 (for thetop and bottom step, for each series of steps) in each side plate are ofa form adapted to fit a cross bar, or rod 7, which supports that seriesof steps.

When the steps 5 are madefrom angle or channel iron a part of theflange, at the point marked 18, may be cut out to make a notch whichengages the terminal opening 2, as shown in Figs. 4 and 5.

The pins or projections in the terminal op'enings 2, project downwardlyfrom the upper side of the openings, and are marked 8 in these openings,and enter openings in the step plates 5, which are held thereon by thecross bars 7 passing under them through the lower part of the opening 2.

The ends of the cross bars 7 are arranged to project sidewise beyond theplates, sufficiently to receive a support in the grooved bracket 9,which bracket may have astem 10, which may be screw threaded or be ofplain cylindric form to fit into openings in a column or upright tube11, or it may be arranged and adapted to enter into the wall of abuilding or other structure. I

The ends of the step plates 5have'perforations 13 and 14, in which maybe inserted the ends of suitable stays or braces upon the wall of abuilding to support the ladders. Into these apertures 13 and 14, mayalso be secured the standards of hand rails.

The side plates 1 are made with definite distances between the apertures2, and may be made with different numbers of steps, so that materialfrom the factory, made in interchangeable parts, may be easily assembledHaving described this invention, what I claim is 1. Side plates havingapertures formed therein provided with projections adapted to engagecorresponding apertures in transverse plates to form steps or ladders,substantially as described and for the purpose set forth.

2. In a metallic ladder the side plate 1, having apertures 2, formed.thereinwith projections 3, in combination with step'plates 5,-havingapertures therein engaging the projections 3, and notched to engage inthe plates 1 1, substantially as described and shown.

3. A step plate for forming metallic ladders consisting of a metallicplate of channel or angle iron, notched on the flanges to engage in theplates forming the sides of the ladders and having apertures 4 adaptedto engage in projections formed in apertures in side plates, and alsohaving perforations 13 and 14 in which are inserted the ends of stays tobrace the latter, said perforations also adapted to receive standards ofhand rails, substantially as described and shown.

4. Side plates 1 and step plates 5, perforated to engage in apertures 2,upon projections 3, in said side plates in combination with cross bars 0tubes 7, arranged to hold the terminal steps in position of engagementwith sideplates 1, substantially as and for the purpose set forth.

5. The side frames 1 and steps 5, perforatedand notched in the mannerdescribed,

in combination with the cross bar and brackets 9 arranged to support theseveral parts as assembled and erected in the form of ladders,substantially as set forth.

6. A sectional ladder construction consisting of side plates 1, havingapertures adapted to engage terminal step plates and cross bars asdescribed, in combination with intermediate step plates having aperturesand projections adapted to engage other perforations in the side plates1 substantially as and in the manner set forth.

